1. Field of the Invention
The present invention relates to interconnection systems for interconnection of elements of digital systems, and more particularly to an electronically controlled interconnection system for selectively interconnecting a plurality of computers with a plurality of peripheral devices.
2. Description of the Prior Art
In recent years, the use of digitized electrical data signals in a wide variety of applications has increased enormously. This has been due to the relatively low cost, high reliability, and high data rates that modern technology has developed. Most large businesses of all types utilize computers which are required to receive digital data from a variety of input devices such as magnetic discs, tapes, keyboards, and similar sources and are also required to transmit digital data to terminals, printers, and other recording equipment. Industrial organizations utilize process control systems and equipment in which analog signals from sensors and the like are digitized for input to controllers. Similarly digital signals are utilized for remote control of the various controlled equipments. The same techniques are often applied to monitoring and control of heating and air conditioning in large buildings. In the medical field, large hospitals will monitor life support systems, and patient responses and activities through centralized computers and alarm systems. It is common to utilize digital techniques for such applications.
One of the problems in all of these large and complex digital systems is that of interconnecting peripherals to central computers and controllers. In most cases, flexibility is required in that the same peripherals are not always required with the same computer or controller. Therefore, means must be provided to disconnect peripherals from the central units and reconnect in other configurations. It is known to utilize patch panels, somewhat analogous to a telephone switchboard, in which multiconductor cables and plugs are used to provide interconnects. There are a number of obvious disadvantages to this approach. First, the personnel must have training and technical skills. Second, the personnel must manually make the connects and disconnects which, due to the complexity of some systems, may not be in a convenient location. The jack fields necessarily have large numbers of contacts which creates problems with high resistance contacts, breakage of pins, and relatively short life when frequent changes are required.
Other approaches include the use of automatic switches and relays which may be remotely controlled. However, these systems also suffer from the mechanical problems associated with contacts and require constant maintenance and repair and generally require significant operating power, making failsafe operation costly. Thus, this type of system has a high recurring maintenance cost as well as a high capital investment required.
There is a need for a remotely operated electronic interconnect system having no relays or metallic contacts and that can be manufactured at low cost, that will require a small amount of power, that will not require synchronization, and that will be failsafe with respect to primary power.